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Sonus Sonetto III vs B&W 603 Comparison

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Sonus Sonetto III

Passive Floor-standing | 42-25k Hz

Sonus Faber Sonetto III
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B&W 603

Passive Floor-standing | 48-28k Hz

Bowers & Wilkins 603
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Sonus Sonetto III Sonus Sonetto III
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B&W 603 B&W 603
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Sonus Sonetto III
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B&W 603
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Sonus Sonetto III vs B&W 603 Speaker Comparison

In this review, we will be comparing Sonetto III and BW 603, two Passive Floor-standing speakers from Sonus Faber and Bowers Wilkins.

Let's have a brief look at the main features of Sonus Sonetto III and B&W 603 first before getting into our more detailed comparison.

Sonus Sonetto III Key Specs

  • 3-way Design
  • 1.15" high definition DAD Dome Tweeter
  • 6" Midrange
  • 2 x 6" aluminum cone Woofer
  • 42-25k Hz Frequency Response
  • 89 dB Sensitivity
  • Impedance: 4ohms
  • Power Range:50-250watts
  • Weight:16.00kg
  • Dimensions (H x W x D): 1018.0" x 9" x 12"( 1018.0 x 219.0 x 305.0mm )

B&W 603 Key Specs

  • 3-way Design
  • 1" Tweeter
  • 6" Midrange
  • 2 x 6.5" Paper Woofer
  • 6" Midrange
  • 48-28k Hz Frequency Response
  • 88.5 dB Sensitivity
  • Impedance: 8ohms
  • Power Range:30-200watts
  • Weight:24.14kg
  • Dimensions (H x W x D): 985.0" x 7.4" x 13.3"( 985.0 x 190.0 x 340.0mm )

What size room are the Sonus Sonetto III and B&W 603 speakers good for?

The size of the room in which you are planning to use these loudspeakers is an important decision factor. Here we have compared their suitability to various sizes of environments considering their size and max power parameters:

Listening Environment* Sonus Sonetto III B&W 603
Near-field Bad Bad
Small Room Poor Poor
Mid-size Room Average Good
Large Room Good Good
Very Large Room Average Poor

(* Approximate Room sizes: Small < 100sq. ft / 9 m2, Mid-size: 100-220 sq. ft / 9-20 m2, Large 220-400 sq. ft / 20-36 m2, Very Large: > 400 sq. ft / 36 m2. Average Floor Height: 9" / 2.7m. Typical room sizes differ from country to country, and the actual listening experience changes depending on floor height, room shape, surface materials, listening position, speaker locations, etc.)

In the following sections, we will get into more detail in order to better understand how the Sonus Sonetto III and B&W 603 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.


**This post contains affiliate links, and I will be compensated if you make a purchase after clicking through my links. As an Amazon Associate I earn from qualifying purchases.


Drivers

Both Sonetto III and BW 603 are 3-way speakers.

Driver Sonus Sonetto III B&W 603
Driver Setup 3-way 3-way
Tweeter 1.15-inch 1-inch
Midrange 1 x 6-inch 1 x 6-inch
Woofer 2 x 6-inch 2 x 6.5-inch

Sonetto III features a 1.15" high definition DAD Dome Tweeter , a 6" Midrange and 2 x 6" aluminum cone Woofer with a Crossover frequency at 220 and 3.250 Hz. On the other hand, the BW 603 features a 1" Tweeter , a 6" Midrange and 2 x 6.5" Paper Woofer .

Frequency Response

Sonetto III has a frequency range of 42-25k Hz whereas BW 603 has a frequency range of 48-28k Hz. With a minimum frequency of 42Hz, the Sonetto III can go significantly deeper on the low side and provide stronger bass compared to the BW 603's min frequency of 48Hz.

Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Floor-standing class in our database.

Low Frequency

Floor-standing Speakers

Sonetto III
BW 603
Min
Average
Max
High Frequency

Floor-standing Speakers

Sonus Sonetto III
B&W 603
Min
Average
Max

None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.

Impedance and Sensitivity

Sonetto III is a 4 ohms speaker compared to the BW 603 which has a nominal impedance of 8 ohms. Lower impedance speakers, especially the ones that are rated at 4 ohms may put more pressure on the amplifier unit especially when played at high volume levels, so make sure the amp you pair with the Sonetto III can provide this impedance level.

These two speakers also have different sensitivity levels. Sonetto III sensitivity is rated at 89 dB and the BW 603's is rated at 88.5 dB.

Sensitivity

Floor-standing Speakers

Sonetto III
BW 603
Min
Average
Max

Power Range

Power range is the range of input power in watts RMS that a loudspeaker is designed to handle. While using an amplifier within this range ensures the nominal performance , inputting a power that is higher than the max wattage can result in a damaged speaker.

Sonetto III can handle a max power of 250 watts RMS from the amp the whereas BW 603 has a max power handling value of 200 watts RMS, 50 watts less than the Sonetto III.

Keep in mind that a higher max power handling value doesn't necessarily make that a louder speaker compared to a lower max handling speaker. Loudness or the sound level is also impacted by parameters such as Impedance, sensitivity and system efficiencies.

Input Type and Bi-Amping / Bi-Wiring

Both Sonetto III and BW 603 features dual binding post speaker terminals for bi-amping or bi-wiring.

Sonus Sonetto III Terminals
Sonus Sonetto III's Binding post terminals allows Bi-amping or bi-wiring

Cabinet Type and Port Position

Sonetto III has a bottom firing port whereas BW 603 has a rear firing ports. Sonus Sonetto III's bottom-firing port gives more flexibility in placement in regards to proximity to walls compared to B&W 603 with its rear-firing port.

Physical Specs

Size of a speaker can sometimes become an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Sonus Sonetto III's and B&W 603's external dimensions. Sonus Sonetto III has external dimensions of 1018.0 x 219.0 x 305.0mm ( 40 x 9 x 12inch) whereas B&W 603 has external dimensions of 985.0 x 190.0 x 340.0mm ( 38.7 x 7.4 x 13.3inch) .

B&W 603 is 29mm narrower and 33mm shorter than Sonus Sonetto III but it is also 35mm deeper.

Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited. The base surface area of the Sonus Sonetto III is approximately 668.0cm2 / 103.5inch2 and base area of the B&W 603 is approximately 646.0cm2 / 100.1inch2. The Sonetto III requires 3% more surface area than the BW 603 which gives it a small disadvantage on placement in tight spaces.

Weight Comparison

The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The Sonus Sonetto III weighs 16.00kg / 35.2lbs and the B&W 603 weighs 24.14kg / 53.1lbs. This makes the BW 603 51% heavier than the Sonetto III.

Here is a comparison of how Sonetto III and BW 603's weights compare with the average, max and min weights in Passive Floor-standing class.

Weight
All Floor-standing Speakers
Sonus Sonetto III
B&W 603
Min
Average
Max

What's in the Box of Sonus Sonetto III?

Here are the items that are included inside the box of Sonetto III:
  • 8 Spikes
  • 8 Under Spikes
  • 8 Spike locks
  • 2 Masks
  • 2 Fabric dust guards
  • 2 Basis
  • 16 Locking screws
  • 2 Jumpers
  • 1 Allen Wrench
  • 1 Manual
  • What's in the Box of B&W 603?

    Here are the items that come with the BW 603:
  • Floorstanding loudspeaker
  • Grille
  • Plinith (base)
  • 2 Jumper-straps (pre-installed)
  • 4 Rubber feet
  • 4 Spike feet
  • 4 Hex-nuts
  • 4 Screws
  • 4 Washers
  • 4 Lock-washers
  • Two-piece foam port plug
  • Hex-key
  • Manual
  • Bowers & Wilkins brochure
  • Warranty Information

  • Reasons to choose Sonus Faber Sonetto III over Bowers & Wilkins 603
    Max Input Power 250 watts vs 200 watts Handle more power from your amplifier
    Low Frequency Response 42 Hz vs 48 Hz Generates deeper bass

    Reasons to choose Bowers & Wilkins 603 over Sonus Faber Sonetto III

    Nominal Impedance 8 ohms vs 4 ohms Less selective with amplifiers
    Woofer Size 6.5 inches vs 6 inches Larger woofer
    High Frequency Response 28k Hz vs 25k Hz Generates higher frequency
    Height 985mm vs 1018mm Easier to fit in smaller spaces
    Base Surface Area 646cm2 vs 668cm2 Takes less floor space
    Sonus Sonetto III vs B&W 603 Specs Table
    Detailed comparison of specifications
    General Sonus Faber Sonetto III Bowers & Wilkins 603
    Brand Sonus Faber Bowers Wilkins
    Speaker Type Floor-standing speaker Floor-standing speaker
    Power Range 50-250 watts 30-200 watts
    Sensitivity 89 dB 88.5 dB
    Impedance 4 ohms 8 ohms
    Frequency Response 42-25k Hz 48-28k Hz
    Drivers
    Woofer Quantity 2 2
    Woofer Size 6" 6.5"
    Woofer Composition aluminum cone Paper
    Woofer Surround Material n/a Rubber
    Tweeter Size 1.15" 1"
    Tweeter Type high definition DAD Dome n/a
    Aimable Tweeter No No
    Midrange Driver 6" 6"
    Crossover Frequency 220 and 3.250 Hz n/a
    Firing Direction bottom rear
    Physical Specs
    Height 1018.0mm (40.1") 985.0mm (38.8")
    Width 219.0mm (8.6") 190.0mm (7.5")
    Depth 305.0mm (12") 340.0mm (13.4")
    Weight 16.00kg (35.2lbs) 24.14kg (53.1lbs)
    Enclosure Bass Reflex Bass Reflex
    Finish n/a MDF/Vinyl
    Available Colors Wood, White, Black, Wenge Black, White, Oak
    Grille n/a Yes
    Moisture Resistancy No No
    Connections
    Biamp Inputs Yes Yes
    Other
    Parts Warranty 5 Years
    Labor Warranty 5 Years

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